1. Field of the Invention
The present invention relates to the field of mirrors and, in particular, to an adjustable mirror for vehicular use to provide the driver with a wide field of view about his vehicle.
2. Description of the Prior Art
Mirrors have been known to man for many centuries. The mirrors made by the ancient Greeks and Romans were mostly made from polished bronze, but glass mirrors were also known. During the middle ages, a process for backing glass with a thin layer of silver and steel was developed. This enabled the rising middle class people to acquire mirrors.
Today, mirrors are used in a variety of wide ranging applications such as astronomy, space ships, solar devices, vehicles, microscopes, satellite communication devices and medicine. Perhaps the best known application for mirrors, are mirrors for motor vehicles.
Motor vehicles require mirrors in order to provide the driver or operator of the vehicle, the widest possible field of view around his vehicle. This is done for safety purposes since most vehicles, due to structural obstructions, have "blind spots" which prevent the driver from seeing any object which may come near either the rear or sides of the vehicle. For years, the automobile designers have attempted to eliminate these blind spots when designing vehicles. Unfortunately, this objective can never be achieved because of the design of the motor vehicle. Thus, it has been found necessary to mount mirrors in and around the vehicle to enhance the field of view of the driver.
One early attempt to enhance the operator's rear field of view is disclosed in U.S. Pat. No. 2,969,715 to Moseby. Moseby increases the driver's field of view by mounting a very large rear-view mirror to one side of the vehicle. While this increased the field of view, it presented other undesirable structural and safety problems.
Another attempt to overcome this problem is disclosed by Fellmeth, U.S. Pat. No. 2,778,273, issued Jan. 22, 1957. Fellmeth uses a mirror with a flat intermediate portion and a convex edge portion. He mounts the mirror adjacent to the left-hand front door or operator's door so that objects proximate to the side, bottom and rear of the vehicle are reflected in the curved and convex peripheral portion of the mirror. Objects, in the far distance rearwardly, however, are reflected in the medial flat portion. This mirror construction also presents other structural and safety problems.
West in U.S. Pat. No. 2,911,177, issued Nov. 3, 1959, discloses a generally spherical segment-shaped reflecting panel with a flat part insert therein.
King in U.S. Pat. No. 3,104,274; Kalutich in U.S. Pat. No. 3,170,985 and Tobin in U.S. Pat. No. 3,389,952 are further examples of convex rear-view mirrors which are used in combination with larger flat mirrors to enhance the rearward view of the operator of the vehicle. However, all these aforementioned designs have inherent safety and structural problems in that the mirrors generally project a substantial distance outwardly from the vehicle.
Jenkins in U.S. Pat. No. 3,303,396, issued Nov. 10, 1961, discloses a convex rear-view mirror which is mounted inside the vehicle. Jenkins modifies a convex rear-view mirror by gradually increasing the curvature at the ends. This curvature substantially minimizes the distortion of objects. Unfortunately, Jenkins still does not provide a wide enough field of view to eliminate many or most of the blind spots in front of, on the sides and to the rear of the vehicle.
None of the aforementioned prior art mirrors have been successfully employed in school buses to reduce "blind spots" in front of the vehicle. Thus, the National Safety Council has reported 58,000 annual school bus accidents occurring nationally in 1977 and 1978 and approximately 165 fatalities per year. A Kansas Department of Transportation study of these national school bus fatalities pinpoints the contributing factors. From 1975 through 1978, 73 percent of the fatalities were among homeward bound pupils; 60 percent of the pupils were killed by the bus itself; and 47 percent were 5 and 6 years old. These statistics indicate that enhancing the driver's view in front of and around the vehicle could reduce these fatalities.